This disclosure generally relates to an apparatus and method for preventing a migration of soldering materials from an electric terminal into the body of an electric device. In particular, this disclosure is directed to a mounting arrangement and method for mechanically supporting and electrically connecting a tactile switch. The mounting arrangement and method according to this disclosure prevent the migration, via electric contacts projecting from the body of the switch, of solder or flux into the body of the switch.
An evaporative emission control system for a vehicle can include an integrated pressure management apparatus (IPMA). An IPMA is disclosed, for example, in U.S. patent application Ser. No. 09/542,052, filed Mar. 31, 2000, and which is incorporated by reference herein in its entirety. This IPMA can perform several functions including system leak detection. Briefly, a switch can be activated indicating displacement of a pressure operable device in response to a negative pressure level in a charcoal canister. A properly performing, i.e., sealed, evaporative system should at least maintain the negative pressure level. However, if the evaporative system has a large enough leak, the evaporative system will not maintain switch activation. This switch can be a tactile switch that must be mechanically and electrically connected with respect to the IPMA.
It is believed that soldering is one technique for providing a mechanical and electrical connection. Conventionally, a switch includes a plurality of electrical contacts that project from a body. Using known soldering materials, e.g., flux and solder, and methods, the electrical contacts are soldered to electric terminals. However, it is believed that these soldering materials, especially flux, migrate along the electrical contacts to inside the switch through small gaps between the electrical contacts and the body. The presence of these soldering materials inside the switch is believed to adversely affect operation of the switch.
Therefore, it is believed that there is a need to prevent, or at least reduce, the migration of soldering materials.
The present invention provides a mount for an electrical device. The electrical device includes a body and a plurality of electric contacts. The body has a base and at least one lateral face extending from the base. The plurality of electric contacts project a distance from the base. The mount comprises an electric terminal and a platform. The electric terminal is adapted to be soldered to at least one of the plurality of electric contacts. The platform is adapted for spacing at a second distance the base from the electric terminal. The second distance that is substantantially equal to the first distance.
The present invention also provides an arrangement forming a mechanical and an electrical connection. The arrangement comprises an electric switch, a plurality of electric terminals extending parallel to a first axis, and a platform. The electric switch includes a body having a base, and a plurality of electric contacts. The plurality of electric contacts project a distance from the base. Each of the plurality of electric terminals include first, second, and third portions. The first portion has a first rectangular cross-section that is oriented transversely with respect to the first axis. The first rectangular cross-section has a first height measured parallel to a second axis that is perpendicular to the first axis, and has a first width measured parallel to a third axis that is orthogonal to the first and second axes. The second portion has a second rectangular cross-section that is oriented transversely with respect to the first axis. The second rectangular cross-section has a second height measured parallel to the second axis and has a second width measured parallel to the third axis. The second rectangular cross-section is substantially congruent to the first rectangular cross-section. The third portion has a third rectangular cross-section that is oriented transversely with respect to the first axis. The third rectangular cross-section has a third height measured parallel to the second axis and has a third width measured parallel to the third axis. The third height is less than the first and second heights, and the third width is less than the first and second widths. The third portion is soldered to at least one of the plurality of electric contacts. The platform is contiguously sandwiched between the third portion of each of the plurality of terminals and the base of the electric switch. The platform has a platform height measured parallel to the second axis from the third portions to the base. The platform height is substantially equal to the distance the plurality of electric contacts project from the base.
The present invention also provides an integrated pressure management apparatus. The integrated pressure management apparatus comprises a housing, a pressure operable device, a switch, an electric terminal, and a platform. The housing defines an interior chamber, and includes first and second ports that communicate with the interior chamber. The pressure operable device separates the chamber into a first portion communicating with the first port and a second portion communicating with the second port. The pressure operable device permits fluid communication between the first and second ports in a first configuration and prevents fluid communication between the first and second ports in a second configuration. The switch signals displacement of the pressure operable device in response to negative pressure at a first pressure level in the first portion of the interior chamber. The switch includes a body having a base, and a plurality of electric contacts that project a first distance from the base. The electric terminal is soldered to at least one of the plurality of electric contacts. And the platform spaces at a second distance the base from the electric terminal. The second distance is substantantially equal to the first distance.
The present invention also provides a method of preventing a migration of soldering materials from an electric terminal into the body of an electric device. The migration occurs via an electric contact that projects from the body of the electric device. The method comprises providing a surface of the electrical terminal with a depressed surface portion; at least partially overlaying the depressed surface portion with a platform rising toward the surface of the electric terminal; contiguously supporting the body of the electric device on the platform such that the electric contact projects toward the depressed surface portion; and electrically connecting with the soldering materials the electric contact to the depressed surface portion.